The first film to be directed by Leni Riefenstahl. The farmers in a small Dolomite village take the wild young girl Junta to be a witch, fearing her evil eye. Moreover, they consider her to be responsible for the deaths of four young men, who had followed her up Monte Cristallo during the full moon of the night into a mysterious blue light. The painter, Vigo, discovers the secret of the mountain: a crystal grotto which reflects a blue light when the moon shines. Vigo tells the villagers of this hidden treasure. They plunder the grotto, destroying it. Seeing this, Junta jumps to her death on Monte Cristallo.